Mail server authorization smtp. What are POP3, IMAP and SMTP servers

Chances are that most people reading this guide are already familiar with the most commonly used communication technology: email. But have you ever thought about how it actually works? In this article, we will learn how this service works and what POP3, SMTP and IMAP are.

POP3(post office protocol version 3) is often used to communicate with a remote email server and download messages to a local email client and then delete it on the server, for example, Thunderbird, Windows Mail, etc. However, email clients usually offer a choice whether or not to leave copies of messages on the server. If you use multiple devices to send messages, it is recommended to leave this feature enabled, otherwise, on another device you will not have access to sent messages that were not saved on the remote server. It is also worth noting that POP3 is a one-way only protocol, which means that data is taken from a remote server and sent to the local client.

The default POP3 ports are:

Port 110 – port without encryption

Port 995 is an SSL/TLS port, also known as POP3S

Step 2 - Differences between POP3 and IMAP, and what are the ports for IMAP?

IMAP (application layer protocol for accessing email), as well as POP3, is used to receive email messages on a local client, however, it has a significant difference - only the email headers are downloaded, the text of the letter itself remains on the server. This communication protocol works in two directions; if changes occur on the local client, they are transmitted to the server. IMAP has become more popular recently as giant email service providers like Gmail have started recommending it instead of POP3.

The default IMAP ports are:

Port 143 – port without encryption
Port 993 is an SSL/TLS port, also known as IMAPS

Step 3 - SMTP, the protocol for outgoing email communications

Simple Mail Transfer Protocol ( SMTP), is used to communicate with a remote server and then send messages from the local client to the remote server, and ultimately to the message recipient's server. On your email server, this process is controlled by a special service ( MTA). It's worth mentioning that SMTP is used solely for sending messages.

SMTP ports:

Port 25 – port without encryption
Port 465 is an SSL/TLS port, also known as SMTPS

Conclusion

We hope that you now have a clear understanding of how email protocols work and what ports they use. In this tutorial, we learned what POP3, SMTP and IMAP are and what they are used for. For example, POP3 and IMAP are used for the same purposes, but they approach these tasks differently. IMAP leaves the content of the message on the server, and POP3 downloads it to your computer. Also, we found out what the standard ports are for SMTP, POP3 and IMAP.

To work with messages coming to your Mail.ru email account, you can and should use special software - email clients. Such programs are installed on the user’s computer and allow them to receive, transmit and store messages. In this article we will look at how to set up an email client on Windows.

Email clients have a number of advantages over web interfaces. Firstly, the mail server does not depend in any way on the web server, which means that if one fails, you can always use another service. Secondly, using a mailer, you can work simultaneously with several accounts and with completely different mailboxes. This is quite a significant advantage, because collecting all mail in one place is quite convenient. And thirdly, you can always customize the appearance of the email client the way you want.

If you use special software, then consider the detailed instructions for configuring this service for working with Mail.ru email.

Now a new mailbox will appear in The Bat, and if you did everything correctly, you will be able to receive all messages using this program

Setting up the Mozilla Thunderbird client

You can also set up Mail.ru mail on an email client. Let's look at how to do this.

Now you can work with your mail using the Mozilla Thunderbird email client.

Setting up for a standard Windows client

We will look at how to set up an email client on Windows using a standard program "Mail", using the example of operating system version 8.1. You can use these instructions for other versions of this OS.

Attention!
This service can only be used with a regular account. You will not be able to configure your email client from an administrator account.

Wait for a message to appear indicating that the account was successfully added and the setup is complete.

This way you can work with Mail.ru mail using standard Windows tools or additional software. These instructions are suitable for all versions of Windows, starting with Windows Vista. We hope we were able to help you.

You can work with Gmail in third-party email clients, such as Microsoft Outlook or Apple Mail. To do this, you need to enable IMAP access and configure SMTP settings. With IMAP access, you can receive Gmail emails on several devices at once; messages will be synchronized in real time. You can also use the POP protocol to work with mail.

Note. To avoid losing access to your own account, make sure that you do not exceed the traffic limits for the IMAP protocol: no more than 2500 MB per day for downloading and no more than 500 MB per day for uploading. If you need to set up IMAP access to one account on multiple computers, take breaks after setting up on each device.

How to set up IMAP

Step 1: Enable IMAP access

Step 2: Change SMTP and other settings in the client

Provide your client with the data from this table. Find more information about IMAP settings for your client online.

Troubleshooting

Can't log into email client

If you are unable to log into your email client, you may see errors like these:

"The application does not accept username or password."
"Invalid credentials."
It keeps asking for username and password.

Step 1: Check your password

If these problems occur, make sure you are entering the correct password.

Step 2: Try troubleshooting

Update your client to the latest version.
Use the application password. If you're using two-step verification, enter your app password.
Allow unsafe applications. If you use two-step verification, you may need to allow unsecured apps to access your account.
If you recently changed your Gmail password, you may need to re-enter your Gmail account information or re-set up your Gmail account in a third-party client.
If the above steps do not help, open the page https://www.google.com/accounts/DisplayUnlockCaptcha and follow the instructions that appear.
The client may be using an insecure login method. Try logging directly into the Gmail app.
Check to see if your email app is checking your email too often. If this happens more than once every 10 minutes, your application may be blocked.

Error "Too many simultaneous connections"

A maximum of 15 simultaneous IMAP connections are allowed per account. If too many clients are accessing Gmail at the same time, an error will appear.

Templates Update!

The CRM system “Client Base” has functionality for conducting mass mailings. At the same time, in order to carry out mailings, you must have an SMTP server through which letters will be sent.
SMTP server is your mailbox from which letters will be sent through the program
If you are using the SaaS version of the program, then the server for sending letters is already configured and ready to work. If you use a local or web version of the program, or want to add your own mailbox to your SaaS account, then this section of the documentation will be useful to you.

Start setting up
Selecting a server type. Setting up an External SMTP Server
Allow sender spoofing

Start setting up

In order to start setting up the server, you need to go to “Settings” - “Newsletter”

In the new window, go to the “Mailout Settings” tab and click on the “Add Server” button.

After this we get to a window where we need to select the server type

Selecting a server type, Configuring an External SMTP server

Internal SMTP - This item should be selected when the mail server and the program are on the same hosting/server. In other cases, the SMTP server simply will not work. If you select this item, you will only need to enter the address of the mailbox from which the mailing will be made in the program.

External SMTP - This option is worth choosing in most cases. It is used when the mail server and the “Client Base” are located on different servers. It is also possible to add only external SMTP servers to the local version of the program. After selecting the “External SMTP” option, a list of fields for filling in server parameters will open.

Important: all SMTP settings correspond to those that you make when adding a new mailbox to your mail program (for example, in outlook, the bat!, mozilla thunderbird and others).

Sender's address - The address from which letters will be sent. Corresponds to the mailbox address. SMTP server - the address of the SMTP server through which the letter will be sent. In most cases it corresponds to the following form:
smtp.*mail provider address*.
That is, for example, smtp.mail.ru, smtp.rambler.ru, smtp.yandex.ru, smtp.gmail.com, etc.

SMTP port—mail port used by the server. In most cases, port 25 is used. Therefore, if you don’t know which port to specify, use it
Important: In SaaS versions of accounts, you cannot add your own servers operating through port 25. You should use either the standard server that was already added initially, or add your own server using a different port, for example, 465.

SMTP login - Login for connecting to your mailbox. Usually corresponds to the mailbox address.

SMTP password - Password to access your mailbox. Those. This is the password with which you connect to the mailbox through a website or email program.

SMTP Security - If sending using SSL or TLS security certificates is used, then they must be specified here. For example, when using SMTP port 465 for sending, you should select “SSL” in this item.

Allow sender spoofing

Some SMTP servers have the ability to change the sender address when used in mailing. Those. it is possible to send letters, for example, from the address [email protected], and the client will see that the letter came from the address [email protected] and, responding, he will also send a letter to this address. If the SMTP server has such an option, then in setting up the smpt server in the Client Database program, you can enable it by checking the “Allow sender substitution” box. Some mail servers (most often free, such as mail.ru or yandex.ru) prohibit sending letters on behalf of a recipient other than the one specified in the smtp settings. In this case, the sender's address in the mailing template must match the smtp sender's address, or it can be left empty (it will be automatically substituted during mailing).

Important: The "Allow sender spoofing" option will only work on mail servers whose settings allow you to add an SPF record with the necessary settings. Most public mail servers (mail.ru, gmail.com, yandex.ru, etc.) do not provide such functionality.

To send a mailing to clients indicating, for example, your corporate mailbox as the sender's address, you need to specify a “fixed” sender in the mailing template settings. Add your corporate email to the "Sender Address" field. In the "Sender's Name" field, add your company name. And in the mailing settings, allow substitution of the sender for the current smtp server.

If there is no smtp server in the settings that allows substitution of the sender, then the address specified in the settings of the current SMTP server will be automatically substituted for the sender of all letters.

Checking "Mail Delivery System" responses

Additionally, the program has the ability to check responses from the "Mail Delivery System". This feature allows you to receive information during mailing if your letter was not successfully delivered to the addressee. To do this, do the following:

2. After that, in the list of fields that opens, enter information about the server for incoming mail - the email box to which responses from the "Mail Delivery System" will be received. You can obtain these settings from your email provider.

Important: The same data is entered into the IMAP server and IMAP login fields, namely the email address to which all replies will be sent.

3. After making all the necessary changes, click on the “Save” button.

Now, if an error occurs when sending a letter and a letter is generated from the "Mail Delivery System", it will be sent to the mailbox whose parameters you specified.

Limit on the number of emails sent

Starting from version 2.0.3, new parameters have appeared in the SMTP server settings:

Ability to set the maximum number of emails per hour for each SMTP server;

Ability to set a limit on the number of emails per day for each SMTP server.

Based on these parameters, it became possible to track information about current limits, that is, how many letters are left before the limit threshold per hour/day. This can be seen by clicking on the “Distribution Options” tab, where information about the current status will be presented next to the server name.

If the message limit has reached its limit, the corresponding information will be displayed informing the user that the limit has been reached.

When the hourly/daily mailing limit is reached, the remaining letters will remain in the queue for sending in "Active mailings". After an hour/day, their sending will continue.
Important! It is worth noting that in version 2.0.3, mailing was optimized when there are several outgoing mail servers. That is, now there is no sequential pass through all available servers with a pause between them, the distribution goes without pauses from the first allowed server until the limit is exhausted, after which the second allowed server is taken, etc.

Features of setting up the Gmail SMTP server

Starting in March 2015, the “Account Access” option appeared in Gmail mailbox settings. This option allows you to use your mailbox with third-party applications. If this option is disabled, the Client Database program will not be able to use the Gmail mailbox as an SMTP server, and the error “SMTP error: Could not authenticate” will be displayed when sending messages.
In order to enable this option, you need to go to your account settings, and in the “Account Access” section, select “Enable”. After this, you will receive an email with information about the changes made to your account settings.

Examples of setting up SMTP servers

Examples of setting up IMAP servers

On a note!

If you are setting up a registered mailbox on rambler.ru as an SMTP server, then there is a possibility that you will encounter a number of difficulties:

1. Firstly, it is worth considering that the rambler mail provider has distinctive features of SMTP server settings (it has 2 options for the type of outgoing server settings: for example, the outgoing mail server can be either mail.rambler.ru or smtp. rambler.ru).

2. Secondly, such a server has a specific requirement for the content of the “From:” field of the letter: the email address you specified in the mail client settings must match the username with which you log in to the SMTP server.

3. Thirdly, in order for letters to be sent correctly from such a mail server, you need to enable the special option “Send letters through the Rambler-Mail SMTP server” in the personal settings of your rambler.ru mailbox. That is, it requires additional authentication on the outgoing message server.

4. Fourthly, when sending from an already configured server of this type, there is a high probability that the letters will end up as failed with the error: “SMTP Error: Data not accepted.SMTP server error: 5.7.1 Spam message rejected; If this is not spam contact abuse at 550 rambler-co.ru

In other words, this means that when sending messages from your server, its IP gets into the so-called “Black list” (black list) and is marked as a source of spam. And in order to unblock your IP, you will need to write a request to the email address [email protected]. The letter indicates the IP of the server that needs to be unblocked and indicates what measures have been taken to eliminate spam from the server.

MAIL.RU

Let's start with the oldest mail service Mail.ru. After going through a simple and clear registration procedure, you receive a mailbox in any of four domains of your choice (mail.ru, inbox.ru, bk.ru, list.ru). The mailbox size is unlimited, initially equal to 10240 MB, as soon as your mailbox has less than 100 MB of free space, the volume can be increased by another 2 GB.
The maximum size of the letter you send should not exceed 30 Megabytes, the number of letter recipients should not exceed 30.
To configure a local email client using the POP3 protocol, use the following parameters:

Incoming message server POP3 server - pop.mail.ru; port 110 (without encryption) or 995 (with SSL encryption)
smtp.mail.ru; port 25, 587 or 2525 (without encryption) and 465 (with SSL encryption)
, including login, "@" dog icon and domain (for example, [email protected]);

The features of this service include the ability to use a non-standard SMTP port 2525 (in addition to the standard 25 and 587) in the settings to bypass the ban of some Internet providers on outgoing TCP connections on port 25 and, alas, the complete lack of support for the IMAP protocol.
The service does not declare restrictions on mass mailings. However, experimentally the following picture emerged:
after sending 120 letters, there were significant delays in mail delivery (up to 40 minutes), after sending 182 letters, error 553 began to appear (the server does not want to transmit mail), which disappeared after some time (from 5 minutes to an hour) and appeared again after sending letters. After 2 days, restrictions continued to apply. The picture did not change much even after sending responses to the initial mailing (no more than 5 letters per hour). It is not advisable to use the free mail service Mail.ru, like any other free mail services, for any serious mailing.

Yandex Mail

In the Russian segment of the Internet, perhaps one of the most popular free email services is Yandex.Mail.
Immediately after registration, the volume of the mailbox is 10 gigabytes. As soon as there is less than 200 megabytes of free space left in it, the mailbox will automatically increase by 1 gigabyte, provided that the user regularly logs in and logs into the Yandex.Mail web interface using a browser.
Of particular note that for a newly created mailbox you should first allow the use of POP3 and (or) IMAP protocols in the Yandex.Mail web interface before you start working with this mailbox in the mail client. This feature, unfortunately, is a very common reason for refusal to send or receive mail in an absolutely correctly configured email client! Be careful!

So, here are the basic parameters for setting up an email program using the POP3 protocol:

Incoming message server POP3 server - pop.yandex.ru, port 110 (without encryption) or 995 (with SSL encryption)
Outgoing mail server (SMTP server) - smtp.yandex.ru; port 25 or 587 (without encryption) and 465 (with SSL encryption)
The username (login) on the POP server and on the SMTP server is, in this case, the first part of your email address to @yandex.ru, for example, if you registered a mailbox [email protected], then ‘myname’ should be specified as the user name (without ‘@yandex.ru’)
In your account settings, you must specify that the outgoing mail server (or SMTP server) requires authorization;

Basic parameters for

imap.yandex.ru, port 143 (without encryption) or 993 (with SSL encryption);

The maximum message size is 30 Megabytes.

To the features service, you should add so-called “one-time” addresses for your e-mail, which look like “your login + [email protected]”, for example, [email protected] or [email protected]. A message sent to this address will be sent to your mailbox. This feature can be useful in many cases where you don't want to share your real email address.
Another feature— mail aliases (pseudonyms) of your mailbox in the domains @narod.ru, @ya.ru, @yandex.by, @yandex.com, @yandex.kz, @yandex.ua.
You can enable and configure this feature in your account settings on the Yandex.Mail web server. Subsequently, you will be able to receive letters to the aliases you have configured. For example, you created an alias (alias) [email protected] And [email protected]. Letters sent to these addresses will arrive in your mailbox. More detailed information on these features should be found in the corresponding section of the Yandex.Mail help system.

The service also does not declare restrictions on the frequency of sending. During the experiments, it turned out that after sending 90 letters, error 550 occurred; in fact, after that it was possible to send no more than 4 letters per hour. The delivery time for letters did not decrease.
After 2 days, restrictions also continued to apply. On the 3rd day, after generating return letters, the possible delivery speed to new addresses exceeded 80 letters per hour and remained this way for at least a day.

Rambler.ru

Another free email service is provided by the search portal Rambler.ru. Mailboxes in the domains @rambler.ru, @ro.ru, @lenta.ru, @myrambler.ru and @autorambler.ru are available for registration. The initial volume of the box is 500 Megabytes (in fact it turned out to be 512 Megabytes). It can be increased in stages up to 1500 Megabytes. Increasing the volume of the box is possible when the amount of free space is less than 10%.

The parameters for setting up an email client using the POP3 protocol are as follows:

mail.rambler.ru, port 110 (without encryption) or 995 (with SSL encryption);
mail.rambler.ru, port 25 or 587 (without encryption or STARTTLS encryption) and 465 (with SSL encryption);
The username (login) on the POP server and on the SMTP server is full name of your mailbox, including login, "@" dog icon and domain (for example, [email protected]);
In your account settings, you must specify that the outgoing mail server (or SMTP server) requires authorization;

The settings of the mail program using the IMAP protocol are identical, with the exception of the incoming message server:

Incoming message server IMAP server - mail.rambler.ru, port 143 (STARTTLS encryption) or 993 (with SSL encryption);

Unencrypted IMAP connections are prohibited in this service. Features of the settings include the requirement for the contents of the “From:” field of the letter: the email address you specified in the mail client settings must match the username with which you log in to the SMTP server.
The size of files that can be attached to a letter is limited to 20 megabytes.

GMAIL.COM

Mail service of the GOOGLE search engine. The new mailbox has a size of 7659 Megabytes without the possibility of expanding the space (at least the author of the article was unable to find any information about expanding the space for mail in the service’s help system). Only the gmail.com domain is available for registration.
With Gmail, you can send and receive messages up to 25 megabytes in size. The maximum number of recipients in a letter sent through the mail program is limited to 100 addresses, and through the web interface - 500 addresses.
The features of this service include only encrypted connections via the POP3, IMAP and SMTP protocols (and even on port 25 a secure connection is used).
Please pay special attention to the fact that, as in the case of Yandex.Mail, before using a mailbox on gmail.com in an email program, you must first enable the use of POP3 and (or) IMAP protocols in the account settings in the web interface on gmail. com!

To configure an email program using POP3 protocols, use the following parameters:

Incoming mail POP3 server - pop.gmail.com, port 995 (with SSL encryption);
Outgoing mail SMTP server - smtp.gmail.com, port 25 or 587 (STARTTLS encryption) and 465 (with SSL encryption);
The username (login) on the POP server and on the SMTP server is full name of your mailbox, including login, "@" dog icon and domain (for example, [email protected]);
In your account settings, you must specify that the outgoing mail server (or SMTP server) requires authorization;

The settings of the mail program using the IMAP protocol are identical, with the exception of the incoming message server:

Incoming message server IMAP server - imap.gmail.com, port 993 (with SSL encryption);

Another feature of gmail.com is that certain types of files are prohibited from receiving and sending, namely files with the extensions “ade”, “adp”, “bat”, “chm”, “cmd”, “com”, “cpl”, “exe” , "hta", "ins", "isp", "jse", "lib", "mde", "msc", "msp", "mst", "pif", "scr", "sct", " shb", "sys", "vb", "vbe", "vbs", "vxd", "wsc", "wsf", "wsh". Moreover, such files are not accepted (or sent) even inside archive files. However, if necessary, this limitation can be circumvented by placing such files in a password-protected archive.